Irene Maude Mossop was born on 6 December 1904 in Woking, Surrey, England, UK, she was the elder child of Maude Binford Eyre and Robert Mossop, a solicitor, later she had one bothers. She was educated privately.
She started writing very young, and after her father death, she started to publishing as Irene Mossop Girl School's novels. In 1934, she married the recently widowed and ex-RAF officer Charles John Swatridge (1896–1964), they moved to a Devon farm, which her husband ran in a gentlemanly fashion and she continued writing. After her marriage, she started to wrote gothic and romance novels, first as Jan Tempest and later as Fay Chandos. In collaboration with her husband, she published as Theresa Charles, and years later as Leslie Lance, after his husband's death in 1964 she continued using the pseudonyms. In 1950s, she had serious discussions with Alan Boon of Mills & Boon about her novel Without A Honeymoon when she introduced the idea of an illegitimate child, that he felt she would encounter difficulties with the Irish audience. Irene Mossop died on 26 October 1988.